Abstract:

Collapse occurred during the excavation of a connection gallery of a shieldbored tunnel of Guangzhou Metro. Programs such as deephole Soletanche grouting executed from the ground surface, triplefluid highpressure jet grouting columns executed from the ground surface and WSS grouting executed from inside the gallery are selected and countermeasures including installing sealing walls in the left tube of the tunnel and filling water into the tunnel are taken, so as to consolidate the backfilled materials in the collapse area and consolidate the ground around the excavation contour. In the end, the strength and permeability of the consolidated ground meet the design requirements, which provides prerequisite for the further excavation of the connection gallery.

Key words: connection gallery, collapse, soletanche grouting, triplefluid highpressure jet grouting, WSS grouting